1. Field of the Invention
The present invention relates generally to the field of security devices that are attachable to trailer wheel hubs to prevent trailers from being stolen or moved. More specifically, the present invention pertains to a unique device that attaches to the lug thread of a wheel hub to prevent wheel rotation or wheel mounting.
A trailer is a type of unpowered vehicle that is pulled by a powered vehicle. Some typical examples are trailers used to transport goods, boats, horses, or mobile homes. Trailers generally have two to four wheels, and attach to another vehicle by a tongue hitch. A problem inherent to the design of trailers is a lack of security means that locks them in a static position when left unattended. Trailers typically do not come with doors, or a braking system that would allow them to be securely parked. Moving a trailer simply requires connecting a powered vehicle to the tongue hitch and driving the trailer away. This lack of security poses a threat to trailer owners, as unattended trailers are common targets of theft.
The present invention improves upon trailer theft prevention designs by rendering a trailer wheel immobile, while also preventing the installation of a replacement wheel and tire for trailers on a bare hub. The present invention is ideal for use on a mobile trailer, such as a utility trailer, boat trailer, equipment or vehicle trailer, but it can also be used to secure any tire mounted on threaded studs, such as spare tires on an exterior holder or specialty wheels mounted on a standard automobile. The present invention utilizes a locking lug nut that requires a special key for engaging the lug nut, which is surrounded by two stainless steel cylinders that are free to rotate about the lug nut. This design defeats many common methods for removing wheel locks, including rotary and reciprocating cutting tools, along with specialty lug nut removal tools that can engage and defeat a common lock nut. The present invention provides a means to delay a would-be thief by presenting a lug locking design that is considerably more complex to defeat, and causes considerable noise and time to do so.
2. Description of the Prior Art
Several devices have been disclosed in the art that attempt to prevent trailer theft. These devices have familiar design elements that focus on attaching a mechanism to a wheel to prevent the wheel from being removed.
Kane, U.S. Pat. No. 4,639,045 discloses a protection apparatus for lug nuts on a truck wheel. Clips are retained to the wheel by the lug nuts, and a flange extends outwardly away from the base. Attached to the flange is a skirt that protects the lug nuts and bolts. Herrera, U.S. Pat. No. 4,825,669 discloses a locking assembly for fastening a lug nut cover on a vehicle wheel. The mounting bracket and the lug nut cover both have elongated holes that are universal and allow them to fit a large number of lug bolt positions and pitches, as measured from the center of the axle to the center of the lug bolt. A lug nut cover is fitted onto special lug nuts. Stormer, U.S. Pat. No. 6,419,326 discloses a locking lug cover assembly which utilizes an annulus secured by a locking mechanism to specially designed lug nuts or studs of a vehicle wheel for prohibiting access to its lug nuts or studs. A locking mechanism extends through the cross section of the annulus to communicate with the lug nuts or bolts and hold the lug cover securely in place. These devices are designed to protect against wheel removal; however they do not prevent wheel rotation, and therefore afford little protection against trailer theft. They similarly do not describe the elements of the locking mechanism, wherein two concentric and freely-rotating cylinders are provided to thwart cutting tools. As a cutting tool engages the cylinders that surround the specialty lug key, they are free to rotate and are difficult to stabilize with secondary tools.
Several designs disclose a device that prevents wheel rotation. Edmondson, U.S. Pat. No. 5,520,034 discloses a wheel-locking device with a nut shield, a wheel bolt orifice on an attachment plate, and an end of nut shield. In the locking position, the lock rod is locked onto a wheel clamp that hooks over a wheel. Pollard, U.S. Pat. No. 5,301,527 discloses a security device for a trailer wheel that includes elongated wheel lug adapters and a back plate which are mounted with conventional lug nuts to the trailer wheel. Edmondson, U.S. Pat. No. 5,410,897 discloses a wheel-block lock with a chock on a chock end of a lock rod that is lockable in a lock sleeve. The lock sleeve is attached to a lug-cover shaft with a lug cover that is lockable onto a locking foot that is attached to a wheel with a lug nut. These devices are adapted to prevent wheel rotation; however they are easily overcome with bolt cutters, portable torches, and other cut off tools. The materials utilized in the present invention, along with its dual cylinder design, prevent the use of cutting torches to cut therethrough, and likewise prevent a thief from grasping a cylinder and applying a cutting tool thereto.
Along with generic cutting tools, thieves also have access to patented lock removal tools that will quickly defeat many standard types of trailer theft devices. These devices are adapted to be hammered or forcefully engaged over the end of a specialty locking bolt, security thereto. Reverse threading allows the engaged device to unscrew the locking nut without the specialty bit. Because of this, a lock that completely immobilizes a wheel lug nut is needed, and one that surrounds the lock nut with a shroud that defeats many common methods of nut removal. The present invention differs from the prior art in that it utilizes a design that defeats several methods for removing wheel locks, or requires specific tools that create considerable noise and time to defeat.
In addition to a specialty lock that shrouds a lug nut, the present invention is mountable to a bare hub to prevent wheel installation or alternatively to an existing wheel to prevent rotation thereof. This modularity is not known in the art. Many trailer owners will remove the wheels from their trailer as an added means of security for long term storage. To defeat such practices, thieves have been known to carry spare wheels to install on bare hubs. The present invention utilizes a unique design that prevents wheel mounting on a bare wheel hub. By protecting the bare hub of a trailer to prevent wheel installation, there trailer is effectively immobilized. During shorter periods of inactivity, or in situations wherein it is not feasible to remove a wheel from the trailer hub, a wheel securing means is provided to work in conjunction with the same lug nut immobilizing means provided for the wheel hub lock. The design of the present invention substantially diverges in elements from the prior art and consequently it is clear that there is a need in the art for an improvement to existing trailer theft devices. In this regard the instant invention substantially fulfills this need.